1. Field of the Invention
The present invention relates to force control of a robot manipulator.
2. Discussion of the Background
When a robot inserts a part into a hole, the part cannot be successfully inserted if the robot opposes an external force that is applied to a robot manipulator. In order to insert the part, the manipulator has to move so as to follow the external force instead of opposing the external force. In general, a manipulator has to include a force sensor for detecting an external force in order that the manipulator can move in such a manner. However, following movement can be performed without using a force sensor. Techniques to make a robot manipulator follow an external force without using a force sensor are disclosed, for example, in Japanese Unexamined Patent Application Publication No. 06-39760.